A detailed description of the grossly improper communications system Clinton established would have illustrated that she knew full well the risk she was running. A large percentage of the secretary of state’s job involves classified matters. We are not talking merely about the exchange of documents marked classified but, more commonly, constant deliberations about sensitive intelligence in classified documents, briefings, and conversations. Clinton’s willful concoction of a home-brew communications network — not a harried official’s occasional, exigent use of private email for official business, but her rogue institution of a private, non-government infrastructure for the systematic conduct of State Department business — made the non-secure transmission and storage of classified information inevitable.

Horowitz’s fleeting conclusion that the decision not to charge Clinton was rational and not necessarily motivated by political considerations hinges on the assumption that the intent evidence truly was as sparse as the FBI and Justice Department described it. Of course the decision to decline prosecution was defensible, if not incontestable, if one accepts that false premise. And Horowitz does not just accept the premise; he treats it as a background assumption, writing as if there’s no other conceivable way to look at the case.

What made Clinton’s conduct outrageous was not that national-defense officials emailed each other frequently. That happens in every government agency that deals with national security. The unique fact here was that Mrs. Clinton willfully set up a system in which those communications would transit through and be retained on a non-secure system, outside the government’s layers of protection. That system was extraordinarily vulnerable to penetration by hostile actors, a fact of which Clinton was undeniably, intimately aware. (See, e.g., Clinton’s banning of State Department employees from using private email for official business due to security concerns; Clinton’s citing of an ambassador’s use of private email for government business in firing him; Clinton’s acknowledgment that she “received a security indoctrination concerning the nature and protection of classified information”; Clinton’s memoir, Hard Choices, in which she vividly recounts the thorough training she received about protecting intelligence from the omnipresent threat of espionage, including instruction to leave communications devices on planes with batteries removed during her frequent foreign travel, as well as the need to use an “opaque tent” or “a blanket over our head” when she and her staff read “sensitive material” outside the secure U.S. government setting.)

The primary advantage of being a Clinton, or a Democrat generally, is being given the benefit of the doubt. Even when you destroy evidence, as Ted Cruz reminded us in this parody back in '16: